Power semiconductor devices are critical to America's energy infrastructure--all electronics, from laptops to electric motors, rely on them to control or convert electrical energy in order to operate properly. Unfortunately, the performance and efficiency of today's dominant power semiconductor device material, Silicon, suffer at higher power levels and higher temperature. This results in substantial loss of efficiency across our energy infrastructure. Innovative new semiconductor materials, device architectures, and fabrication processes promise to improve the performance and efficiency of existing electronic devices and to pave the way for next-generation power electronics.

Project Innovation + Advantages:

Monolith Semiconductor will utilize advanced device designs and existing low-cost, high-volume manufacturing processes to create high-performance silicon carbide (SiC) devices for power conversion. SiC devices provide much better performance and efficiency than their silicon counterparts, which are used in the majority of today's semiconductors. However, SiC devices cost significantly more. Monolith will develop a high-volume SiC production process that utilizes existing silicon manufacturing facilities to help drive down the cost of SiC devices.

Potential Impact:

If successful, Monolith Semiconductor would improve the performance, lower the cost, and facilitate the widespread use of SiC devices in a variety of power electronics applications, including vehicles and motor drives.

Security:

Advances in power electronics could facilitate greater adoption of electric vehicles, which in turn could help reduce U.S. oil imports.

More efficient power electronics would use less energy, saving American families and business owners money on their power bills.

Innovation Update:

(As of May 2016)

Monolith partnered with X-Fab Texas, a silicon semiconductor manufacturing company, to develop the processes and manufacturing innovations required to fabricate cost-competitive SiC devices. By using the existing silicon manufacturing facility, Monolith dramatically reduced the overhead expenses for manufacturing SiC devices. The resulting SiC device and manufacturing model attracted investment from the Army Research Laboratory, and in December 2015, Monolith announced a strategic partnership with circuit protection device company, Littelfuse Inc. Through this partnership, Monolith will accelerate the development of its technology and help bring SiC technologies to market.

The team had to overcome compatibility challenges between the existing silicon production lines and the needs of its SiC device. The existing fabrication processes and tools for silicon wafers could not handle the optically transparent SiC wafers, requiring Monolith and X-Fab to modify the process to allow transparent SiC wafers on the silicon production line. The team also had to make modifications to ensure the production line could accommodate the more difficult gate oxide formation process for SiC MOSFETs (metal-oxide-semiconductor field-effect transistor). Monolith developed state-of-the-art SiC MOSFET gate oxides, and through a partnership with the National Institute of Standards and Technology (NIST), the team has quantified the long-term reliability of these oxides operating at temperatures up to 300oC. The team is continuing to develop advanced device designs and processes to further reduce costs and improve performance.

For a detailed assessment of the Monolith team's project and impact, please click here.